A. Scuba Diving's Buddy System
Scuba (“Self-Contained Underwater Breathing Apparatus”) diving is a well-known activity practiced by people for applications such as sport, commercial, military, scientific, search and recovery, professional underwater photography and movie making. Because of the inherent risk and unfamiliarity associated with an underwater environment, people wishing to practice scuba diving are required to be trained and certified in diving safety, equipment, environment, communications, procedures, etc.
One of the fundamental safety practices of scuba diving is to never dive alone. A diver should always dive with another diver who remains nearby at all times. Preferably, the two divers should be separated under water by only a few feet. When divers dive in pairs, the divers are practicing what is conventionally called the “buddy system,” wherein each diver is a “buddy” to the other diver. Under the buddy system, the divers have a responsibility to each other. For the buddy system to work, both divers must want it to work and must learn to apply the practices that will maximize their safety and minimize their separation underwater. Further, each diver must constantly be aware of the other diver's situation. Hence, the buddy system increases the safety, as well as the enjoyment, of diving.
The buddy system increases diving safety because a diver's responsibility is primarily to prevent and overcome problems and emergency situations encountered by the other diver, and secondarily to generally assist the other diver, as needed. The problems and emergency situations that can occur underwater include being out of air, trapped, entangled, injured, etc. The general assistance that can be provided above the water includes putting on suits and equipment, checking equipment, removing an entanglement, etc. The general assistance that can be provided underwater includes reminding the other diver of time limits, depth limits, air supply limits, direction, temperature and assent rates, surveying the area for hazards, adjusting the other diver's equipment, assisting with navigation, keeping track of each other, etc. The buddy system also provides a psychological aid to divers because the divers feel more secure, less stress and less likely to panic when another diver is present.
The buddy system increases the diving enjoyment because two divers can share experiences and witness unusual occurrences or discoveries together rather than alone. Because two divers witness more than one diver, one diver can point out something of interest under water that the other diver might have missed.
B. Traditional Scuba Diving Communication
Under water, the buddy system requires that the two divers have some way of gaining each other's attention to initiate communications and then some form of communication with each other. Divers are trained to communicate with each other by using primitive techniques such as predetermined hand signals, an underwater writing slate, making noise by banging on the air tank with a hard object, or by tugging on a line held by each diver. However, a disadvantage of both the hand signals and writing slates is that they rely almost entirely upon the divers maintaining line of sight with each other. Various unavoidable circumstances related to diving break the line of sight between the divers to render the hand signals or messages on the writing slate inadequate to gain the attention of the other diver. Such circumstances include the orientation of the divers' bodies or heads relative to each other, limited visibility through a mask or the water, separation beyond an arm's length distance, water currents, etc. A disadvantage of banging on the air tank is that a diver may not always have tools or devices for making sufficient noise under water that will attract the attention of the other diver. Further, since sound travels in all directions under water, a diver would not only gain the attention of their buddy diver, but also inadvertently gain the attention of other non-buddy divers in the vicinity of the tank. A disadvantage of tugging on a line is that the line limits the mobility between the divers and a diver's necessary mobility in the water can cause the line to be accidentally tugged. All of these circumstances can result in a breakdown of the buddy system to decrease the divers' safety and enjoyment during the dive. Over the years people have proposed various devices to improve upon these traditional communication techniques.
C. Alert Systems
1. Single Diver Alert Systems
a. Single Diver Surface Alert Devices
Traditionally, scuba divers have relied on whistles to gain someone's attention on the water's surface. However, if a scuba diver is disabled and can't blow into the whistle, the whistle makes no sound at all. Further, if a scuba diver needs to attract the attention of someone who is too far away from to hear the whistle, then the whistle is of no help.
A Dive Alert™ device is a small, lightweight air horn that uses quick connect/disconnect hose fittings to become an integral part of a diver's power inflator used to inflate a scuba diver's buoyancy control device (BCD) using compressed air from the scuba diver's air tank. When the scuba diver presses a button on the Dive Alert™ device, the button engages a chrome-plated brass actuator valve stem causing a small amount of air to rush by a stainless steel diaphragm causing a piercingly loud sound to be emitted from an injection-molded thermoplastic body to gain someone's attention on the water's surface up to one mile away from the scuba diver. The Dive Alert™ device is better than the whistle when that a diver's air tank has enough air for the Dive Alert™ device to operate. However, both the Diver Alert™ device and the whistle share a disadvantage in that a diver would not only gain the attention of their buddy diver, but also inadvertently gain the attention of other non-buddy divers in the vicinity of the Dive Alert™ device.
b. Single Diver Underwater Alert Devices
A Sub Alert™ device is a small, lightweight air horn that includes a Sub Alert™ unit and a low-pressure hose to generate an underwater signal using compressed air from the diver's air tank. When the scuba diver presses a button on the Sub Alert™ device, the Sub Alert™ device generates an underwater signal that can be heard up to 25 feet away when the other diver is wearing a hood.
U.S. Pat. Nos. 4,635,242 and 5,010,529 disclose audible electronic signaling devices worn by a single diver and used to gain the attention of another diver in the vicinity. However, these patents do not teach or suggest a receiving device worn by another diver.
The Sub Alert™ device and the audible electronic signaling devices disclosed in U.S. Pat. Nos. 4,635,242 and 5,010,529 share the same disadvantage as the surface alert devices in that the alert not only gain the attention of their buddy diver, but also inadvertently gain the attention of other non-buddy divers in the vicinity. In some cases, a pair of divers or a small team of divers would like a discreet signal that will gain the attention of another diver without disturbing other divers in the vicinity.
2. Diver-to-Diver Alert Systems
U.S. Pat. Nos. 3,469,231 and 5,523,982 and publications WO 98-17526 and WO 98-45969 disclose diver-to-diver alert systems having a transmitter and a receiver, wherein each diver wears an alert system. These patent and publications disclose alerting a diver with an audible, a visual or a vibrating alert. These patent and publications also disclose that the alert system is carried on a diver's wrist, forearm, arm or waist. The patents and the publications do not teach or suggest that the transmitter, the receiver or the alert is carried on a diver's mask. The audible alert shares the same disadvantage as the surface and underwater single diver alert devices in that the audible alert not only gain the attention of their buddy diver, but also inadvertently gain the attention of other non-buddy divers in the vicinity. A disadvantage of the visual alert is that the visual alert would not immediately gain the attention of the diver if the diver does not constantly look at the visual alert on their wrist, forearm, arm or waist. Typically, divers dive with their head up to see where they are going and their arms at their sides to reduce water resistance. Hence, the diver's natural diving position is not conducive to monitoring a visual alert on their wrist, forearm, arm or waist. A disadvantage of the vibrating alert is that the vibrating alert conveys a very limited amount of information intended by the diver transmitting the alert signal, since the vibrating alert can only vibrate or not vibrate.
D. Underwater Wireless Voice Communication Systems
1. Single Diver Voice Communication Systems
Ocean Technology Systems (oceantechnologysystems.com) manufactures diver recall system called a DRS-100B Diver Recall/Hydrophone that is used on some charter dive boats. The diver recall system permits a diver on the boat to alert, to recall or to send voice communications to divers under water. The diver recall system generally includes an electronic package, a power supply, located on the boat, and a transducer, located in the water. All divers within range (e.g. 100 yards) of the transducer hear the communications with their naked ear and therefore have no need for an electronic listening device. Although the diver recall system is appropriate for general boat to diver communications, the diver recall system shares the same disadvantage as the surface and underwater single diver alert devices and the diver-to-diver audible alert devices in that the alert or voice communications gains the attention of all divers in the vicinity of the recall system.
2. Diver-to-Diver Voice Communication Systems
Various companies provide systems for underwater voice communication between two or more scuba divers. Ocean Technology Systems, Inc. (http://www.oceantechnologysystems.com) provides underwater communication systems including hard-wire, through-water, sonic, wireless, diver recall systems, Buddy Phone®, Aquacom®, Hot Mic®, and Buddy Line®. Another company, Ocean Reef (http://oceanreefgroup.com), provides an underwater communication system, called “Neptune”, having a mask, called a Neptune II, integrated with a regulator, called a NIRA (Neptune integrated regulator adapter), and a communication system, including a GSM (Global submarine messenger) ultrasound transceiver/receiver, a model M101A receiver unit, and a model M105 surface unit. Yet another company, Stone electronics ltd. of B.C. Canada using distributor, Scubapro (http://www.scubapro.com), provides an underwater communication system, called “Dive-Link®” (http://www.divelink.net), including a surface unit, a two way diver communicator, a diver listen only model and communication options for various full face masks provided by other companies. The Dive-Link® system includes a headpiece, having a transceiver, a battery, a switch, an audible signal generator and mask straps, and a mouth piece electrically coupled to the headpiece. The mask straps attached to a conventional mask. The switch has an on, off and emergency position. When the switch is in the emergency position, the audible signal generator produces a loud beep that can be heard by all divers in the vicinity of the audible signal generator. Although these voice communication systems provide improved underwater voice communications over those of the past, these systems remain relatively expensive due to relatively complicated voice communication circuitry. For example, for sport divers, the Buddy Phone® system model XT-100 is advertised at a price of $340.00 and the Dive-Link® system is advertised at a price of $649.00.
E. Underwater Wireless Data Communication Systems
1. Single Diver Wireless Data Communication Systems
U.S. Pat. Nos. 5,191,317, 5,899,204 and 6,054,929 disclose data communication system including a transmitter, carried by a diver's air tank, and receiver, carried by the same diver's wrist or mask, for communicating data from the diver's air tank to the same diver's wrist or mask. However, these patents do not teach or suggest a data communication system including a transmitter, carried by a first diver, and receiver, carried by a second diver.
2. Diver-to-Diver Wireless Message Communication Systems
U.S. Pat. No. 6,125,080 discloses diver-to-diver message communication device having a transmitter and a receiver, wherein each diver wears a message communication device. The message communication devices, carried by each diver, forms a communication network in which each diver can communicate preset data messages with any one of the other divers in the network or with a base station. The message communication device has belts (shown as straps with buckles) for attaching the device to a diver's hand, to another part of his body, his diving suit, or his own equipment. The message communication device also has a liquid crystal display (LCD) and a buzzer or vibrator for notifying a diver of an incoming message. However, this patent does not teach or suggest that the belts attach the data communication device to the receiving diver's mask in a manner that permits the receiving diver to view the LCD.
F. Dive Mask, Swimmer's Goggles or Eyeglasses Having a Visual Display or Indicator
U.S. Pat. No. 4,999,606 (dive mask), U.S. Pat. No. 5,191,317 (dive mask), U.S. Pat. No. 5,301,668 (dive mask), U.S. Pat. No. 5,685,722 (swimmer's goggles), U.S. Pat. No. 5,162,828 (eyeglasses), and publication WO 00/55676 (eyeglasses) disclose a display or indicator carried on a dive mask, swimmer's goggles or eyeglasses, respectively. However, these patents and the publication do not teach or suggest that the display or indicator is controlled or activated responsive to a signal transmitted by a transmitter carried by another diver.
G. Conclusion
Accordingly, scuba divers, practicing the buddy system, have a long-felt but unsolved need for an underwater alert system that increases the safety, as well as the enjoyment, of diving. The underwater alert system would be a practical, safe, inexpensive, simple, easy to use and reliable system. The underwater alert system would provide a substantial improvement over the traditional scuba diving communication techniques and yet cost much less than the underwater wireless voice communication systems. The underwater alert system would permit one scuba diver to discreetly and immediately gain the attention of another scuba diver, unlike many of the conventional underwater alert systems, and yet not be as complicated as the underwater wireless data communication systems. Alternatively, the underwater alert system would be a two-way system to permit each scuba diver to discreetly and immediately gain the attention of the other scuba diver. Further, alternatively, the underwater alert system would interface with a scuba diver's dive computer to permit dive computer data to be communicated from one scuba diver to another scuba diver.